In the processing of liquid metals, it often is necessary to elevate the liquid metal from one location to another. Such elevation is conventionally carried out by linear induction machines or mechanical impeller pumps.
Such linear induction systems employ open troughs which are subject to oxidation as well as permitting a head of only about one meter. The liquid metal is not pressurized and hence transport stops immediately outside the magnetic zone.
Circular linear motors have been employed to elevate liquid metals in tubes with the limitation that the velocity can be induced only in a limited outside peripheral area of the tube, causing a reverse flow down the center. In addition, the velocity heads created are very low.